In order to achieve a maximally space-saving stand configuration, stands having energy storage elements dispense with a counterbalancing arm configured as a counterweight, or a counterweight that is located opposite a horizontal support of the stand.
Conventional stands with gas-spring bracing have proven successful, but are used only in stands that exhibit moderately homogeneous movement. Different types of bracing, for example the balance-like weight/counterweight system, are used for stands that need to be used over a larger movement space and/or with more convenient movement guidance.
Conventional gas-spring-braced stands have the disadvantage that because of the so-called “cosine function” of the load lever effect of the microscope along its vertical movement arc, the bracing effect that is present differs as a function of the angular position of the horizontal support with respect to the vertical support. The force on the gas spring acting as the supporting lever is also greatest with the stand in the pivot position in which the load is located farthest away from the vertical support when the horizontal support and vertical support form a right angle.
EP-B1-433 426 describes a compensating apparatus, having a gas spring as the energy storage element, that encompasses an arc-shaped or kidney-shaped elongated guidance hole on the vertical support in which the proximal end of a piston rod is guided, while the cylinder constituting the distal end of the gas spring is secured pivotably on the horizontal support. (In the remainder of this Application, “proximal” means “toward the vertical support” and “distal” means “away from the vertical support, toward the unattached end of the horizontal support”.) This construction with an arc-shaped elongated guidance hole is theoretically intended to prevent the hysteresis of the gas spring from becoming disadvantageously perceptible. “Hysteresis” is understood in general to mean the dependence of the physical state of an object on previous states, based on a residual effect (remanence) after removal of the applied physical magnitude or force.
It has been found in practical use, however, that this known configuration is disadvantageous in that the proximal end of the piston rod does not move continuously in the arc-shaped elongated guidance hole but instead, when used, jumps from one extreme position to the other in the manner of a toggle lever; for a user, this requires an additional movement across the jumping point in order to achieve readjustment of the support conditions in the arc-shaped elongated guidance hole.
An optimally balanced-out stand that is homogeneously pivotable in the vertical exhibits an equality between the weight torque and support torque. An inequality between these two torques is expressed, for the operator, in two disadvantageous ways: either the microscope moves by itself into a different location, or for one range the operator requires one specific pivoting force in order to move the microscope, but then suddenly a different force. The optimum, desirable equality between the weight and support torques does not really exist, however, because of actual physical or geometrical circumstances, but exists only for a certain range. That range can be in the middle of the overall pivot angle range, or at the margins; but with the known stand approaches using energy storage elements a compromise is always arrived at between the optimum and disadvantageous range. In the existing art, an attempt is made to minimize this compromise by, for example, keeping the weight fluctuations at the microscope as low as possible, keeping the pivot angle as small as possible, or concealing the difference in torques within an elevated system friction. These actions, however, place limits on the stand design.
The optimum range is usually placed in the middle of the overall pivot angle range, which corresponds approximately to a horizontal position of the horizontal arm. The result, when depicted in a diagram of the difference in torques, is a wave-shaped curve such as FIG. 6a (pivot force curve function). There are, however, stand settings that make the optimum range of equality between the weight and support torques available, for example, in the lower pivot angle range. In this case the curve corresponds to a non-wave-shaped, arc-shaped function curve with appended straight lines, for example FIG. 6b. 
The inventor has recognized that once the proximal articulation point for the widest possible optimum range of equality between the torques has been discovered or calculated, a deliberately effected slight adjustment of the proximal articulation point, to the detriment of the optimum range, results in a considerable reduction in the maximum difference between the torques. This result is unexpected, since one would necessarily have assumed that a displacement of the optimum articulation point would result in an even greater difference between the torques. The maximum difference decreases, however, and substantially (i.e. by more than half). The magnitude of this improvement is also unexpectedly high. As the diagram depicts, the wave-shaped curve is transformed into a saddle-shaped curve, and the arc-shaped function curve with attached straight lines is transformed into a new curve having a substantially lower amplitude.